The invention relates to polygalacturonides and to the use thereof. Polygalacturonides are oligosaccharides obtained e.g by enzymatic decomposition of pectins. Pectin has galacturonic acid monomers or galacturonic acid (methyl)ester monomers as major components. Typically, both monomers are present at the same time, the esterification level of the galacturonic acid groups ranging from 0.5% to 70%. The galacturonic acid monomers or ester monomers are xcex1-1,4-linked to each other. In particular regions of the pectin molecule, however, rhamnose monomers are inserted in the chain, resulting in a zigzag structure of the polymer. The rhamnose monomers may have side chains attached thereto which may be formed of arabans (xcex1-1,5 linkage) and arabinogalactans (linkage: xcex2-1, 3-1, 6-D). The side chains may also include other sugar monomers. As a supplement, reference is made to the xe2x80x9cFlxc3xcssiges Obstxe2x80x9d Jun. 1997, pp. 301. This citation also describes that the use of pectinases in juice production for clarification purposes gives rise to undesirable colloids which interfere with further processing and must be removed or prevented. In natural unfiltrated juices, on the other hand, it is only the pectins rather than the fragments thereof which have an advantageous influence on the viscosity. It is clear from these considerations that in juice production, for example, the presence of pectin fragments is undesirable for technical reasons.
In addition to technical aspects, pectins also involve physiological aspects. The citation Cerda, J. J., Trans. Am. Clin. Climatol. Assoc. 99, 203-213 (1987), describes that pectin from grapefruits plays an important role in promoting health in consumers. The citation Matsumoto, T. et al, Int. J. Immunopharmacol. 15, 683-693 (1993), describes that particular fragments of Bupleuran 2IIc, a pectin-like poly-saccharide from the roots of Bupleurum falcatum, might be highly important in pharmaceutical terms. The fragments are obtained by reaction with endo-polygalacturonase (EC 3.2.1.15). Ultimately, the citation Voragen, A. G. J., Trends Food Sci. Technol. 9, 328-335 (1998), provides information that non-digestible polysaccharides or oligosaccharides may have a number of health-promoting effects on persons consuming same.
Producing oligosaccharides for pharmaceutical purposes from pectins using pectinases is known from the citation U.S. Pat. No. 5,683,991. The pectinases used therein are mixtures of various enzymes which possibility also include endo-polygalacturonase (EC 3.2.1.15), so that cleavage also is effected in the side chain regions. Moreover, the ester groups are hydrolyzed prior to reacting with the pectinases so that, as a result, comparatively small oligosaccharides (2-4 monomers) are obtained.
Additives in the food industry are to fulfill a variety of functions. Essential functions are in the sector of preparing processed foodstuffs, e.g. with respect to consistency, durability and color appearance.
The invention is based on the technical problem of providing an additive for foods which would improve the foods in a health-promoting respect, with respect to taste, and optionally with respect to consistency and/or other consumer-related properties.
To solve said technical problem, the invention teaches the use of polygalacturonides as additives in goods, said polygalacturonides being obtainable via the following process steps:
1. a pectinous plant material is subjected to a pectin extraction is aqueous solution;
2. the solids are removed from the suspension obtained in step a), consisting of liquid phase including dissolved pectin and solids from the plant material;
3. the pectin is precipitated from the liquid phase obtained in step b);
4. the pectin obtained in step c) is dissolved in an aqueous solution and cleaved with purified endo-polygalacturonase (EC 3.2.1.15);
5. the polygalacturonides obtained in step d) are processed into a polygalacturonide preparation with using an additional separation step and without hydrolyzing ester groups that are present.